The present invention generally concerns a sheet feeder apparatus and more particularly a document handling mechanism for feeding documents individually and selectively from a stack thereof into associated document processing apparatus, such as a photographic instrument for recording the visual indicia appearing thereon.
Several different types of document feeder devices are known in the prior art. One such device is described in U.S. Pat. No. 2,992,820 to Tarbuck et al. A number of difficulties have been associated with the particular document feeders known heretofore. Among such difficulties has been the inability to provide an apparatus which will accommodate documents of varying thickness, if at all, without troublesome adjustments and delays resulting in expensive down time. Another material disadvantage of such prior art sheet feeder systems has been the necessity of removing and replacing various components of the apparatus during initial loading thereof with the sheets to be fed.
In many such prior art document feeders, unless frequent adjustments were made, the feeding pressure varied sufficiently greatly from document to document during individual document feeding to promote jamming. Still other prior art feeders have required several manual steps in their operation which resulted in slow and inefficient operation. Yet another of the feeder devices known heretofore have lacked means for automatically adjusting the feeder for documents of various thicknesses, which has greatly reduced the versatility of the device and increased the operational cost to the consumer.
Each of the aforementioned defects and/or difficulties ha reduced the commercial acceptance, usability and saleability of prior art feeder devices. Accordingly, it is an object of the present invention to alleviate materially the above noted deficiencies of the prior art and to provide an improved document feeder apparatus.
It is another object of the present invention to provide a spring driven document feeder which is equipped with a brake mechanism operable in response to a pivotable arm engaging the documents and moveable from a first position to a second position to close and open a switch controlling the brake mechanism.
It is also an object of the present invention to provide a document feeder apparatus in which the nip between drive and reverse rollers may be controlled or completely disengaged for the processing of documents of various thicknesses by providing lever-ended shaft means for pivoting one such roller.
These and other objects and features accomplished by the present invention will be better understood with reference to the following summary of the invention, drawings and detailed description thereof.